The Multidisciplinary Association for Psychedelic Studies, or MAPS for short, is conducting a series of tests to find out if the illegal drug MDMA, also known as Ecstasy, could be used to treat Post Traumatic Stress disorder. If approved, the drug could become legal and available for treatment starting in 2021.

Business Insider recently talked to Chris Kilham, a "medicine hunter" who travels the world searching for natural remedies through medicinal plant research. We asked Kilham to break down the history of MDMA, and what MAPS hopes to accomplish with their Phase III study.